• 제목/요약/키워드: direct manipulation

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Efficient baseline suppression via TIP and modified DEPTH

  • Hyun, Namgoong
    • 한국자기공명학회논문지
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    • 제26권4호
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    • pp.51-58
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    • 2022
  • The baseline flattened NMR spectrum has been achieved by several methodologies including pulse manipulation with a series of phase cycling. The background signal inherent in the probe is also main source of baseline distortion both in solution and solid NMR. The simple direct polarization with 90° pulse flipping the magnetization from the z-axis onto the receiver coil requires the strong rf pulse enough to encompass the wide frequency range to excite the resonance of interest nuclei. Albeit the perfect polarization 90° pulse, the signal from the unwanted magnetic fields such as background signal can not be completely suppressed by suitable phase cycling. Moreover, slowly baseline wiggling signal from the low 𝛾 nuclei is not easy to eliminate with multiple pulse manipulation. So there is still need to contrive the new scheme for that purpose in an adroit manner. In this article new triple pulse excitation schemes for TIP and modified DEPTH pulse sequence are analytically examined in terms of arbitrary phase and flip angle of pulse. The suitable phase cycling for these pulse trains is necessary for the good sensitivity and resolution of the spectrum. It is observed that the 13C sensitivity TIP experiment is almost equal to the CP/MAS with modified DEPTH sequence, both of which are applicable to both solid and solution state NMR.

본드선도를 이용한 동적시스템의 직접 종합방법 (Direct synthesis method of dynamic systems in terms of bond graphs)

  • 박전수;김종석
    • 대한기계학회논문집A
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    • 제22권2호
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    • pp.399-407
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    • 1998
  • This paper deals with a method for finding the physical structure of dynamic systems which shows reasonable response to a given specifiation. The method uses only four basic models of bond graph prototypes which have been originally proposed by the authors as a general model for dynamic systems, and then makes its procedure highly physical in the sense that it can synthesize a dynamic system through the structural transformation directly on bond graph models without any mathematical manipulation. Also, it is shown that this method has further advantages in optimizing parameters for an existing system rather than developing design concepts for a new device, the latter being more suitable using the so-called analytical synthesis method introduced by Park and Redfield. One example serves to trace the outlines of the direct synthesis method proposed in this paper for dynamic systems in terms of bond graph prototypes.

경두개 직류전류 자극이 대뇌피질의 뇌 활성도에 미치는 영향 (Cortical Activation in the Human Brain induced by Transcranial Direct Current Stimulation)

  • 권용현;김중선;장성호
    • The Journal of Korean Physical Therapy
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    • 제21권4호
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    • pp.73-79
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    • 2009
  • Purpose: Recently, neurostimulation studies involving manipulation of cortical excitability of the human brain have been increasingly attempted. We investigated whether transcranial direct current stimulation (tDCS) applied to the underlying cerebral cortex, directly induces cortical activation during fMRI scanning. Methods: We recently recruited five healthy subjects without a neurological or psychiatric history and who were right-handed, as verified by the modified Edinburg Handedness Inventory. fMRI was done while constant anodal tDCS was delivered to the underlying SM1 area?? immediately after the pre-stimulation for eighteen minutes. Results: Group analysis yielded an averaged map that showed that the SM1 area and the superior parietal cortex in the ipsilateral hemisphere were activated. The voxel size and peak intensity were, respectively, 82 and 5.22 in the SM1, and 85 and 5.77 in the superior parietal cortex. Conclusion: Cortical activation can be induced by constant anodal tDCS of the underlying motor cortex. This suggests that tDCS may be an effective therapeutic device for enhancing? physical motor function by modulating neural excitability of the motor cortex.

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Strategies to Mitigate Enteric Methane Emissions from Ruminant Animals

  • Tseten, Tenzin;Sanjorjo, Rey Anthony;Kwon, Moonhyuk;Kim, Seon-Won
    • Journal of Microbiology and Biotechnology
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    • 제32권3호
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    • pp.269-277
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    • 2022
  • Human activities account for approximately two-thirds of global methane emissions, wherein the livestock sector is the single massive methane emitter. Methane is a potent greenhouse gas of over 21 times the warming effect of carbon dioxide. In the rumen, methanogens produce methane as a by-product of anaerobic fermentation. Methane released from ruminants is considered as a loss of feed energy that could otherwise be used for productivity. Economic progress and growing population will inflate meat and milk product demands, causing elevated methane emissions from this sector. In this review, diverse approaches from feed manipulation to the supplementation of organic and inorganic feed additives and direct-fed microbial in mitigating enteric methane emissions from ruminant livestock are summarized. These approaches directly or indirectly alter the rumen microbial structure thereby reducing rumen methanogenesis. Though many inorganic feed additives have remarkably reduced methane emissions from ruminants, their usage as feed additives remains unappealing because of health and safety concerns. Hence, feed additives sourced from biological materials such as direct-fed microbials have emerged as a promising technique in mitigating enteric methane emissions.

An instrumented Glove for Grasp specification in virtual reality based point-and-direct telerobotics

  • Yun, Myung-Hwan;Cannon, David;Freivalds, Andris
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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    • pp.141-146
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    • 1996
  • Hand posture and force, which define aspects of the way an object is grasped, are features of robotics manipulation. A means for specifying these grasping "flavors" has been developed that uses an instrumented glove equipped with joint and force sensors. The new grasp specification system is being used at the Pennsylvania State University (Penn State) in a Virtual Reality based Point-and-Direct(VR-PAD) robotics implementation. In the Computer Integrated Manufacturing (CIM) Laboratory at Penn State, hand posture and force data were collected for manipulating bricks and other items that require varying amounts of force at multiple pressure points. The feasibility of measuring desired grasp characteristics was demonstrated for a modified Cyberglove impregnated with FSR (Force Sensitive Resistor) pressure sensors in the fingertips. A joint/force model relating the parameters of finger articulation and pressure to various lifting tasks was validated for the instrumented "wired" glove. Operators using such a modified glove may ultimately be able to configure robot grasping tasks in environments involving hazardous waste remediation, flexible manufacturing, space operations and other flexible robotics applications. In each case, the VR-PAD approach improved the computational and delay problems of real-time multiple-degree-of-freedom force feedback telemanipulation.ck telemanipulation.

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State-selective Dissociation of Water Molecules on MgO Films Using LT-STM

  • Shin, Hyung-Joon;Jung, J.;Motobayashi, K.;Kim, Y.;Kawai, M.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.112-112
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    • 2011
  • The interaction of water molecules with solid surfaces has been a subject of considerable interests, due to its importance in the fields from atmospheric and environmental phenomena to biology, catalysis and electrochemistry [1,2]. Among various kinds of surfaces, a lot of theoretical and experimental studies have been performed regarding water on MgO(100), however, to date, there has been no direct observation of water molecules on MgO by scanning tunneling microscope (STM) as compared with those on metal surface. Here, we will present the direct observation and manipulation of single water molecules on ultrathin MgO(100) films using low-temperature scanning tunneling microscope (LT-STM) [3]. Our results rationalize the previous theoretical predictions of isolated water molecules on MgO including the optimum adsorption sites and non-dissociative adsorption of water. Moreover, we were able to dissociate a water molecule by exciting the vibrational mode of water, which is unattainable on metal surfaces. The enhanced residual time of tunneling electrons in molecules on the insulating film is responsible for this unique pathway toward dissociation of water.

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The Effect of Ownership Structure on Transfer Pricing Decisions: Evidence from Foreign Direct Investments in Vietnam

  • TRAN, Quoc Thinh;TRAN, Mai Uoc;LUU, Chi Danh
    • The Journal of Asian Finance, Economics and Business
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    • 제8권12호
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    • pp.183-189
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    • 2021
  • Transfer pricing is a matter of concern for countries. It affects the interests of the parties involved in the commercial transaction. Through manipulation of prices in transactions, businesses take advantage of tax rates in a country to adjust profits for economic gain. This affects the fairness and rationality of economic transactions between related parties. The article uses a two-year time series from 2018 to 2019 of 50 foreign direct investment enterprises in Vietnam. The article uses ordinary least squares to test the hypotheses of the research model. The article uses four independent variables related to ownership structure affecting transfer pricing decisions including total ownership, organization ownership, concentration ownership, and area ownership. Research results show that two variables have a positive influence on transfer pricing decisions including total ownership and organization ownership. Organization ownership has a higher degree of influence than total ownership. To be able to control transaction activities related to transfer pricing, Vietnam's state management agencies need to pay attention to perfecting the legal framework based on supplementing and amending regulations related to transfer pricing. Legal regulations need to be regulated based on international common practices to ensure uniformity on a global scale.

학교 급별에 효과적인 계절별 별자리 실험에 대한 예비교사의 인식 연구 (Research on the Perception of Pre-service Teachers on Effective Seasonal Constellation Experiment according to School Level)

  • 한제준
    • 대한지구과학교육학회지
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    • 제14권3호
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    • pp.267-276
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    • 2021
  • 이 연구의 목적은 계절별 별자리 실험에 대해 알아보고, 학교 급별로 효과적인 계절별 별자리 실험이 무엇인지 연구하는데 있다. 초등 예비교사 24명과 함께 계절별 별자리 실험을 정리하고, 학교 급별로 효과적인 실험이 무엇인지 쓰도록 하였다. 그 결과 초등학교에서는 역할놀이를 통한 직접적인 체험활동을 통한 별자리 학습이 가장 효과적이었고, 중·고등학교에서는 stellarium 프로그램을 이용하여 사실적으로 계절별 별자리의 변화를 관찰하고 추리해보는 활동을 효과적인 실험으로 선택하였다. 예비교사는 초등학교에서는 직접적인 체험과 구체적인 조작활동이 강조되는 실험을, 중·고등학교에서는 사실적인 자연현상의 관찰과 이를 통한 추리 활동이 강조되는 실험이 효과적이라고 인식하였다.

An instrumented glove for grasp specification in virtual reality based point-and-direct telerobotics

  • Yun, Myung Hwan;Cannon, David;Freivalds, Andris
    • 대한인간공학회지
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    • 제15권2호
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    • pp.165-176
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    • 1996
  • Hand posture and force, which define aspects of the way an object is grasped, are features of robotic manipulation. A means for specifying these grasping "flavors" has been developed that uses an instrumented glove equipped with joint and force sensors. The new grasp specification system is being used at the Pennsylvania State University (Penn State) in a Virtual Reality based Point-and-Direct (VR-PAD) robotics implementation. In the Computer Integrated Manufacturing (CIM) Laboratory at Penn State, hand posture and force data were collected for manipulating bricks and other items that require varying amounts of force at multiple pressure points. The feasibility of measuring desired grasp characteristics was demonstrated for a modified Cyberglove impregnated with FSR (Force Sensitive Resistor) pressure sensors in the fingertips. A joint/force model relating the parameters of finger articulation and pressure to various lifting tasks was validated for the instrumented "wired" glove. Operators using such a modified glove may ultimately be able to configure robot grasping tasks in environments involving hazardous waste remediation, flexible manufactruing, space operations and other flexible robotics applications. In each case, the VR-PAD approach improved the computational and delay problems of real-time multiple- degree-of-freedom force feedback telemanipulation.

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그래프에 기반한 전역적 정합 방법 (Graph-Based framework for Global Registration)

  • 김현우;홍기상
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 제13회 신호처리 합동 학술대회 논문집
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    • pp.671-674
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    • 2000
  • In this paper, we present a robust global registration algorithm for multi-frame image mosaics. When we perform a pair-wise registration recovering a projective transformation between two consecutive frames, severe mis-registration among multiple frames, which are not consecutive, can be detected. It is because the concatenation of those pair-wise transformations leads to global alignment errors. To overcome those mis-registrations, we propose a new algorithm using multiple frames for constructing image mosaics. We use a graph to represent the temporal and spatial connectivity and show that global registration can be obtained through the search for an optimal path in the constructed graph. The definition of an adequate objective function characterizing the global registration provides a direct manipulation of the graph. In the presence of moving objects, especially large ones compared with low texture backgrounds, by using the likelihood ratio as the objective function, we can deal with some of the most challenging videos like basketball or soccer Moreover, the algorithm can be parallelized so it can be more efficiently implemented. Finally, we give some experimental results from real videos.

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